Effect of aluminum substitution on the structure, electrochemical performance and thermal stability of Li_1+x(Ni_0.40Mn_0.40Co_0.20−zAl_z)_1−xO₂

Laurence Croguennec (1) , Jessica Bains (1) , J. Bréger (2) , Cécile Tessier (2) , Ph. Biensan (2) , Stéphane Levasseur (3) , Claude Delmas (1)

1 ICMCB - Institut de Chimie de la Matière Condensée de Bordeaux
2 SAFT [Bordeaux]
3 UMICORE Research

Li_1.04(Ni_0.40Mn_0.40Co_0.20−zAl_z)_0.96O₂" (z = 0; 0.05 and 0.10) samples were synthesized using a coprecipitation method followed by calcinations at 500°C for 5 h and then at 950°C for 2 h. Structural and physico-chemical characterizations have shown that these materials were obtained pure with a small overlithiation ratio (Li/M = 1.01-1.03) and thus a significant exchange between the divalent nickel ions from the slabs and the lithium ions from the interslab spaces (between 4% for the non substituted material and 8% for the aluminum substituted ones). Aluminum substitution induces a decrease of the reversible capacity, but also a major improvement of the thermal stability in the deintercalated state (corresponding to the charge state of the battery). These results have thus shown that the composition Li_1.01(Ni_0.39Mn_0.40Co_0.15Al_0.06)_0.99O₂ is very attractive for large scale lithium-ion batteries to be developed for EV and HEV applications.

Mots clés: Calcination; Lithium compounds; Precipitation; Secondary cells; Thermal stability

Domaines: Matériaux

Laurence Croguennec, Jessica Bains, J. Bréger, Cécile Tessier, Ph. Biensan, et al.. Effect of aluminum substitution on the structure, electrochemical performance and thermal stability of Li_1+x(Ni_0.40Mn_0.40Co_0.20−zAl_z)_1−xO₂. Journal of The Electrochemical Society, 2011, 158 (6), pp.A664-A670. ⟨10.1149/1.3571479⟩. ⟨hal-00586359⟩